With the sudden increase in temperature, the hot summer has arrived, and there are more and more parents consulting on sun protection for children in the clinic during this period of time, so I will summarize some common questions here. 1.What do the SPF and PA marked on the sunscreen mean? SPF (Sun Protection Factor) refers to the sun protection factor, also known as the sun protection index, which generally represents the level of sun protection effectiveness that sunscreens can play. In other words, the higher the SPF value, the longer the duration of protection. Specifically, if a person has no protection and the skin starts to show redness after 15 minutes of sun exposure, if you choose a sunscreen with SPF 30, your safe time under the sun is 15 x 30 = 450 minutes, and so on. Of course, there are some individual differences in the tolerance of children’s skin in the sun. So the kind of sunscreen you choose will depend on the amount of time you spend outdoors and the intensity of the sun. For children playing indoors, most sunscreens with SPF 15-25 are fine. But when playing outside, it is best to use sunscreens with SPF 30 or more. pa++ (Protection UVA) is an indicator of how far UVA is prevented. although UVA is not easy to sunburn skin, but can cause photoaging, so it is also an important component of sunscreen. pa has three levels of defense, namely pa+, pa++, pa+++. Simply put SPA value is the index of sunburn prevention, and PA value is the indicator of anti-skin tanning and sun aging. For example: SPF30 and PA++ if it appears on the packaging of a bottle of sunscreen, it suggests that: this bottle of sunscreen can effectively protect against sunburn within 300 minutes, and it is quite effective in defending against UVA. 2.What types of sunscreens are available on the market? Which ones are suitable for children? How old can children use sunscreen? At present, sunscreens are mainly divided into physical and chemical sunscreens: physical sunscreens work by refracting and scattering UV rays. Physical sunscreens are not known, that is, they put a layer of protective clothing on the skin, and the ultraviolet rays that hit the surface of the skin are blocked outside and cannot enter the skin. The common physical sunscreen agents are titanium dioxide, zinc oxide, etc. The advantage of physical sunscreen is high safety, good stability, but the disadvantage is that the texture is slightly thick, applied to the skin surface is easy to whitish. Physical sunscreen, there is another advantage, that is, apply that sunscreen, no need to wait. Chemical sunscreens work differently from physical sunscreens by absorbing UV rays and converting them into heat, thus preventing UV damage to the skin. The advantage of chemical sunscreens is that they are light and non-sticky, but the disadvantage is that they are not photostable and need to be reapplied repeatedly under prolonged sun exposure. Moreover, chemical sunscreens need to be applied about 20 minutes before going out in order to exert their sun protection effect. Currently, most sunscreen products on the market use a physical sunscreen + chemical sunscreen formula in order to take into account both the lightness of the sunscreen and the immediate effect. Most children are recommended to apply physical sunscreen better and with fewer side effects. However, for babies above June, you can use some safe mixed sunscreen as appropriate, such as Avène sunscreen. 3.What are the manifestations of sun exposure in children? What kind of manifestations must be seen by the hospital? After sun exposure in spring and summer, minor manifestations are edematous erythema with clear boundaries, mostly bright red, with obvious itching; in severe cases, blisters, blisters, ulcers, erosion, self-conscious burning and stinging sensation is obvious. The former can be applied cold and wet at home, and if necessary, some glucocorticoid ointment or most ointments for “eczema” can be applied topically. However, the latter is more serious and needs to be treated by the dermatology department of a regular children’s hospital in a timely manner. After treatment, most children’s skin lesions become darker, flaky and leave pigmentation, which takes several months to fade and recover. If the sun exposure is longer than ten hours, it may be accompanied by conjunctival congestion, eyelid edema, and even systemic symptoms such as fever, chills, fatigue, nausea, and general malaise. 4.Do you do skin test before using sunscreen? No special instrument testing is needed, but some children have allergic performance to sunscreen. It is recommended that when using a brand of sunscreen for the first time, it should be applied topically to the skin on the forearm or behind the ear of the child first, and overnight, no redness, swelling, itching and other discomfort can be used on a large area. 5.Does my baby need to take off sunscreen after coming back indoors from outdoors? It is necessary to “remove the makeup”. Generally speaking, you can wash it with water. If the sunscreen is greasy, feel that water washing is not clean, you can choose baby soap or baby cleanser.